Psu making noise when pc is off

Feb 18, 2018
42
0
30
My new corsair rm750x psu is making a low electrical buzzing noise when my pc is turned off. Is this dangerous? Can this mean that my psu is damaged?
 
Feb 20, 2018
5
0
10
The PSU might be damaged or there is a problem with your electric circuit unit. It might be dangerous don't touch your circuit. Call some technicians in.
 

JalYt_Justin

Reputable
Jun 12, 2017
1,164
0
5,960
I would suspect that you have a dying or faulty PSU and I would try to RMA it. Any noise outside of coil whine is cause for a problem.

Even if it's not damaged or faulty, the fact that it's making an electrical buzz is enough to constitute an RMA. Better safe than sorry.
 
Feb 18, 2018
42
0
30


Ok. Butt if I cant rma it will it kill other components if it dies? Its a corsair rm750x psu and it has a lot of different protections.
Over-voltage protection, under-voltage protection, short circuit protection, over power protection, and over temperature protection
 
make sure you used the mb standoffs and the io shield not shorting out the mb. check that none of your cables have been cut by the case doors or are pinched. if the unit under 30 days return it to where you got it. if you rma you may not get a new unit.
 
Feb 18, 2018
42
0
30

what do you mean? The sound comes from the psu. Do you think ist dangerus?
 
Feb 18, 2018
42
0
30


Burn down my house?
 
with power the sound can be a bad ground or bad cap and coil. check that none of the power supply wires are cut or pinched. number one new builder error is pinching or cutting cables on the back side of the mb. another issue with new builders is the eps cable most new builders run it over the cpu and gpu. it can get wires caught in the fans or melt from the heat.
 
May 5, 2019
2
0
10
Hi Tobias,
what about your PSU?

during 1 month I analyse a lot of PSU, and you know what? All that I have tested do the same " buzzing , coil whine , or other zzzzz" and I think it is normal!

All begin when I decided to change my motherboard , only cosmetic reasons .. I had gigabyte z370HD3P with i7 8700K ( I never OC) and I change for ASUS Z390E , then I decided to buy a better PSU ( I had evga 600B , 1 year , 100h max ..)
After a lot of search, tier list, reviews, I choice corsair RM650X, receives my Rog mobo and the corsair, mounted 1 day with lot of attention, then power on! and all seems good, no noise.. I power off, and put my head behind the PSU!! zzzziiziiiziiiziiiziii , when pc is on this sound dissapear. and when pc is on standby this sound is more important.
I had time to send it to seller, but after a lot of labour to mount cables .. I decided to contact corsair, they answer after 3 days " your rma was accepted" , I asked them again " why? , I don't want to rma it" they say " this psu is faulty" I asked " which one I have to buy? all your psus RM are faulty? a remplacement will resolve this issue??, they don't answer.
I return this rm650x to seller ( lost 10 eur)
I try an EVGA 650 G+ , the better that EVGA made by FSP group.
result: the fan is too loud, always 750 rpm. and I listen ziiiiiii when the psu is working on game. RETURNED

then I try my chance with an RM750x ( made by TWC, the 650x is made by seasonic)
result : exactly the same, perhaps a little silent ziiii than the 650x , but this one is doing this noise when on and off,
If I don't put my ear behind the psu I heard nothing ,

I asked corsair again, but I think that all this psu doing that " electrical noise" that not means they are faulty, I hope...

I don't say my last word, I don't know if I will keep this rm750x , I don't need so much power , i7 8700k and rtx2060 max Watt is near 400W .. 550w is enought
 

Karadjgne

Titan
Ambassador
When the pc is off, normally the psu should be off too, however there are sometimes ports like certain USB that will remain active for bios upgrade, USB wakeup, Lan wakeup, USB charging etc. This'll mean the psu is not actually off when the pc is. Most times (unless there's a physical switch on the psu) the only way to guarantee a psu is off is to unplug it.

It should not be making noise, period. What you'll have to decide is whether to contact Corsair or not because it's more than likely still covered by the factory warranty, regardless of any vendor warranty. Under the kinds of load at pc off state, it should be dead silent, there's not enough activity to even spin the fan, it's a passive load throughput.

Is it dangerous? That's unknown. Corsair psus have a really nasty habit of dieing quietly, they don't explode as such, especially at the RM level of quality. So even a dead short doesn't go anywhere.
 
May 5, 2019
2
0
10
Yes I know that when pc is off the mobo still uses psu for usb .. and when I activate ERP ( eco mode) the psu stop buzzing, but I hear a little buzz when I put my head behind psu.

perhaps a lot of people have this sound but they don't make difference.

this is the 3rd psu that I try, and the same issue, I think it's " normal"

I will try an other one , the last one! from à other seller, because when I bought the rm650x it was cheaper ( 85 eur) and after 1 week it was sold 99eur, are they do this price for " bad units" ?
this was the same when I bought the rm750x, it was cheaper than 650x! 92 eur when 650x is 99 eur

1 week later, now the rm750x is 130 eur...
they epure the bad units??
 

Karadjgne

Titan
Ambassador
Possibly, they might just test it, it works, so stick it back on the shelf. Easier on them than returning to manufacturer. Or maybe they bought a batch of returns at a discount from someone else, you have no way of knowing because the store definitely will not tell you if it did anything shady.

But normally the Corsair RMx is an excellent psu